CROSS-REFERENCE TO RELATED APPLICATIONS
TECHNICAL FIELD
[0002] The present invention relates to a handling unit for moving a mold closing element
of a forming machine for producing hollow glass articles.
BACKGROUND
[0003] As is known, forming machines, universally known as IS machines, are used to form
hollow glass articles.
[0004] Such machines comprise a plurality of forming sections arranged side by side, into
each of which a succession of drops of glass enters and from each of which a succession
of formed hollow glass articles exits.
[0005] Each molding section comprises a blank mold and a finishing mold arranged downstream
of the blank mold. Both molds can have a single forming cavity or a plurality of forming
cavities arranged next to one another.
[0006] Regardless of the number, each forming cavity is open in an upward direction and
must be closed fluid-tight at the top during the forming phase of the glass article.
[0007] Each cavity is accordingly provided with a related closing element which extends
vertically and closes the related cavity completely in the case of blank molds, or
partially in the case of finishing molds, thus allowing a flow of compressed forming
air to be introduced into the finishing molds from above.
[0008] The closing elements of a same mold are carried by a dedicated supporting head, which
is connected to a free end of an arm. The arm extends in a cantilever manner from
a motorized vertical drive shaft, and is coupled to said shaft by means of a respective
attachment clamp fixed to the column by means of clamping screws.
[0009] The vertical shaft and, together with the latter, the related arm are vertically
movable in order to move the related closing elements between a raised resting position
and a lowered operating position, in which the related closing elements are coupled
to the respective mold in a fluid-tight manner.
[0010] As is known, IS machines are set up to be provided with different molds depending
on the article to be produced. These molds have different dimensions and, in particular,
different heights.
[0011] Therefore, at each mold change, the height position of the closing elements must
be adjusted according to the height of the mold that will be mounted on the machine
and so that the closing elements are always coupled tightly to the mold when arranged
in their lowered operating position.
[0012] Adjustment is currently carried out manually by a team of responsible operators,
who, at each mold change, demount the closing elements and mount the respective setting
templates, known in the jargon as "callipers" or "face mold", in their stead.
[0013] Each face mold is dimensioned so as to couple with the mold on the machine in exactly
the same way as the related closing element and has a height that is less than the
height of the related closing element so as to take into account the inevitable deformations
of the handling unit under working conditions.
[0014] The use of face molds is rendered necessary and indispensable by the fact that the
closing elements end, at the bottom, in sharp edges that would be damaged during the
manual adjustment in the event of an accidental contact or collision of the closing
elements with the new mold, and in any case if they are not arranged exactly in the
intended correct operating position.
[0015] Once the face molds are mounted, still manually, the clamping screws of the clamp
are loosened under the control of one of the responsible operators and the arm and
the related head lowered or raised until the face molds are coupled to and in abutment
with the related mold underneath.
[0016] Once this position has been reached, which is assumed as the new reference height
position, the clamp is, still manually, tightened again on the vertical shaft, effectively
rendering the arm integral with said vertical shaft, after which the face molds are
demounted and, in their stead, the closing elements dedicated to the new mold are
mounted on the machine.
[0017] As mentioned above, the foregoing steps are repeated manually at each mold change
and for both molds in each of the forming sections.
[0018] Although universally implemented, the above-described manner of setting the closing
elements is hardly satisfactory for the following reasons.
[0019] First of all, it is immediately obvious how this makes it necessary, for each mold
that can be mounted on the machine, to have on hand a plurality (one for each mold
cavity) of face molds, with imaginable costs both in terms of the manufacture as well
as the storage and handling of said face molds.
[0020] Moreover, the setting of the closing elements of the entire forming machine requires,
at each mold change, extremely large amounts of time which increase with the number
of sections due to the aforementioned mounting, demounting and remounting operations,
with inevitable losses in terms of production.
[0021] As mentioned above, the foregoing operations require, for each mold in the section,
at least a pair of responsible operators. This is because at least one of the operators
has to support the arm-head assembly while the other operator loosens the clamping
screws of the clamp and both accompany the arm and related head during the vertical
repositioning. The loosening of the screws, the accompanying of the head and the correct
positioning and coupling of the face molds to the related mold are operations that
require experience and considerable coordination between the operators inasmuch as
they must be conducted so as to avoid a jamming of the clamp on the shaft due to the
fact that the arm and the head protrude in a cantilever manner from the vertical shaft.
[0022] The foregoing operations are also rendered difficult by the fact that the operators
are forced to work while standing above the base of the machine and straddling the
related molds and thus in awkward and dangerous working conditions.
[0023] In all cases, a significant and prolonged physical effort is required of the operators
and, in general, the aforementioned operations inevitably involve a very long downtime
of the machine.
SUMMARY OF THE INVENTION
[0024] The aim of the present invention is to provide a handling unit for moving a mold
closing element of a forming machine that allows the problems set out above to be
solved in a simple and cost-effective manner.
[0025] A particular aim of the present invention is to provide a handling unit that allows
an adjustment of the closing elements to be carried out quickly, extremely safely
and precisely while eliminating operator discretion.
[0026] A further aim of the present invention is to provide a handling unit that allows
drastically reducing or at least simplifying manual operations, reducing or eliminating
the physical effort required of operators, as well as reducing the number of operators
responsible for such adjustments so as to minimize operating costs and machine downtime.
[0027] A last aim of the present invention is to provide a handling unit which is simple
and cost-effective to produce, compact and which can be inspected and operated from
the outside.
[0028] According to the present invention, a handling unit for moving at least one mold
closing element in a machine for forming glass articles is provided, as defined in
the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] The invention will now be described with reference to the accompanying drawings,
which illustrate a non-limiting embodiment thereof, wherein:
Figure 1 illustrates, in a partially and substantially block layout, a forming machine
for forming glass articles equipped with a preferred embodiment of a handling unit
for moving closing elements of the forming machine, which handling unit is embodied
in accordance with the teachings of the present invention;
Figure 2 illustrates, in an elevation side and perspective view, the handling unit
of Figure 1;
Figure 3 is a figure analogous to Figure 2 and illustrates a variant of a detail of
Figure 2;
Figure 4 illustrates, on a larger scale, a detail of Figure 2;
Figure 5 illustrates, on a larger scale, a variant of a detail of Figure 2; and
Figure 6 illustrates a connection coupling of Figure 2 broken down into its constituent
parts.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0030] In Figure 1, a forming machine for forming glass articles, generally known as an
IS machine, is indicated, as a whole, by 1.
[0031] The machine 1 comprises a plurality of forming sections 2, only one of which is visible
in the attached figures.
[0032] Each forming section 2 comprises a blank mold 3 comprising, in this specific case,
four forming cavities 4 arranged side by side and open in an upward direction and
a finishing mold 5 also comprising four finishing cavities 6 open in an upward direction.
[0033] According to variants not illustrated, the molds 3 and 4 comprise a different number
of cavities 4,6.
[0034] Regardless of the number of cavities 4,6, the machine 1 further comprises a closing
assembly 8 for closing the cavities 4 of the blank mold 3 and a closing assembly 9
for closing the cavities 6 of the finishing mold 5 and configured to allow compressed
air to be introduced into said cavities 6.
[0035] With reference to Figure 2, the assembly 8 comprises a supporting head 10 and, for
each cavity 4, a closing element 11, known
per se and not described in detail.
[0036] Each closing element 11 is coupled to the head 10 in a manner known
per se, protrudes vertically downwards and is configured to couple with the mold 3 in order
to completely close the related cavity 4.
[0037] Each assembly 8 further includes a handling unit 13 for moving the head 10 and the
related closing elements 11.
[0038] The unit 13 comprises a dedicated attachment frame 14 fixed to a structure 15 of
the machine 1 in proximity of the blank mold 3 (Figure 1).
[0039] The unit 13 further comprises a related drive shaft 16, which has a vertical axis
18, a straight upper end section 19 projecting upwards beyond the frame 14 and a lower
end section (not visible in the attached figures) coupled to a drive device K, known
per se and not described in detail, for moving the shaft 16 with a roto-translatory motion
along the axis 18.
[0040] The unit 13 finally comprises a slide 20 coupled to the section 19 so as to be slidable
along the axis 18 in opposite directions, and an arm 21 that supports the head 10
and extends orthogonally to the axis 18.
[0041] Preferably, the slide 20 can be locked manually from the outside by means of a dedicated
wrench acting, for example, on a screw 20A.
[0042] Alternatively, the slide 20 is locked on the section 19 by means of a motorized locking
device, e.g., of a mechanical friction or magnetic type and in any event a device
that can be controlled from outside the machine or remotely.
[0043] The arm 21 comprises a free end portion 22 firmly connected to the head 10 and an
attachment end portion 23, opposite the portion 22 and coupled to the slide 20 by
means of a releasable coupling 24 for the quick replacement of the arm-supporting
head assembly.
[0044] Conveniently, the coupling 24 comprises a vertical guide 25 parallel to the axis
18 and firmly connected to the slide 20, and a slide 26 firmly connected to the attachment
portion 23 and couplable from above to the guide 25. The slide 26 is clamped on the
guide 25 in a releasable manner by means of a clamping screw 27, which can be actuated
manually from the outside by means of a dedicated wrench. Alternatively, the slide
26 is locked on the guide 25 by means of a motorized locking device, e.g., of a mechanical
friction or magnetic type and in any event a device that can be controlled from outside
the machine or remotely.
[0045] With reference to Figure 4, the slide 20 is movable along the section 19 under the
thrust of a mechanical transmission 30, which in the described example is of a screw
type. Alternatively, the mechanical transmission 30 is a toothed transmission or some
other equivalent linear transmission.
[0046] The transmission 30 comprises a screw 31 arranged outside the section 19 of the vertical
shaft 16 and coupled to the vertical shaft 16 in a rotatable manner about its axis
31A and in an axially fixed position, and a nut screw 32 engaged by the screw 31 and
coupled to the slide 20 in a vertically and angularly fixed position with respect
to said slide 20.
[0047] Again with reference to Figures 2 and 4, the screw 31 is rotated by an electric motor
35. Conveniently, the transmission 30 comprises an attachment bracket 36, in turn
comprising an anchoring portion 37 arranged resting on an upper end of the shaft 16
and an attachment portion 38 protruding in a cantilevered manner from the anchoring
portion 37. The screw 30 is coupled to the attachment portion 38 in a rotatable manner
and in an axially fixed position, protrudes upwards beyond said attachment portion
38 and is firmly connected to the rotor of the motor 35.
[0048] Conveniently, the motor 35 extends upwards from the attachment portion 38, to which
it is firmly attached.
[0049] Still with reference to Figure 2, the electric motor 35 is commanded and controlled
by a command and control unit 40.
[0050] The unit 40 comprises a memory block 40A storing, for each mold 3,5 that is installable
on the machine 1, a respective reference position of the closing elements 11, i.e.
their correct height position, and a command and control block 40B for controlling
the motor 35 and moving the closing elements 11 into the reference or operating positions
depending on the mold currently mounted on the machine 1.
[0051] Conveniently, each unit 40 communicates with a general machine unit 41 that synchronizes
the position adjustment activities of all relevant closing elements 11 by controlling
all of said closing assemblies in response to a mold change program.
[0052] Again with reference to Figure 1, each assembly 9 is similar to the assembly 8 described
in the foregoing, from which it differs only by comprising, instead of the head 10,
a head 43 that supports closing elements 45.
[0053] The closing elements 45, also known
per se, differ from the elements 11 in that they couple to each cavity 6 fluid-tightly and
respectively define a respective compressed air supply duct within the related cavities
6.
[0054] The head 43 further differs from the head 10 in that it carries ducts 45A for supplying
compressed air to the respective closing elements 45.
[0055] In the variant illustrated in Figure 3, the screw 31 is rotated about its own axis
31A by acting manually from the outside on a motion input shaft 46, which is part
of a worm screw - worm gear transmission 47, fixed to the portion 19 of the shaft
16 by means of a collar 48 (Figure 2). The shaft 46 extends orthogonally to the axis
31A outside the arm 21 and slide 20, and the transmission 47 forms part of the transmission
30.
[0056] It is evident from the foregoing that the use of a slidable slide along the section
19 of the vertical shaft 16 and the presence of the transmission 30 allow a single
operator responsible for the section 2 to correctly position the closing elements
11,45 at each mold change in an extremely short period of time, simply by acting from
the outside on the shaft 46 by means of a common crank or manoeuvring wrench or by
controlling the motors 35 via the units 40, and without the need to intervene on the
device K that drives the shaft 16.
[0057] In any case, the precision and continuity with which the arms 21, and with them the
related heads 10,43, are moved, allow a single operator to carry out the height adjustment
at a mold change without the need to demount and remount the closing elements 11,45
from the related heads 10,43 and, above all, compared to known solutions, to be able
to adjust the height of the closing elements 11 and 45 without having to use "face
molds", which can consequently be completely eliminated, thus fundamentally solving
all the problems linked with the handling and storage of the same.
[0058] In particular, during the adjustment performed by the transmission 30, the arms 21
only move with a translatory motion, i.e. they translate while remaining parallel
to themselves, so that the spatial orientation of the closing elements 11,45 is not
altered.
[0059] Using the 35 motors also practically eliminates the physical effort required of operators
inasmuch as they can operate remotely on the individual section 2 or simultaneously
on the entire machine in response to an issued mold change command.
[0060] Compared to known solutions, the physical effort is reduced even without the motors
35 inasmuch as the adjustment is limited to the mere rotation of a crank or wrench
couplable to the shafts 46 that protrude at the front and thus in an area easily accessible
from the outside and without the need to climb up onto or down from the surface supporting
the molds, i.e. while remaining outside the forming section, with considerable advantages
in terms of safety.
[0061] Again compared to known solutions, the presence of the drive motors 35 and the presence
of the related command and control units eliminate the arbitrariness of the movement
as there is a transition from little more than a visual control on the part of the
operator to a fully automatic control of the individual section 2 or of the entire
machine 1 on the basis of information stored in memories or databases, for example
in said command and control unit.
[0062] The presence of the motors 35 and the screw-nut screw transmission 30 facilitates
an extremely precise and gradual positioning of the closing elements 11,45, thus preventing
any damage to said closing elements during the mold change phase.
[0063] It is also evident from the foregoing that the provided handling units 13 are simple
in design, cost-effective and, above all, extremely compact as well as being immediately
inspectable from the outside.
[0064] The compactness and simplicity of the design also allow the described closing assemblies
8,9 to be used on existing forming machines without requiring any particular modifications
or adaptations of said machines.
[0065] It is evident from the foregoing that the described closing assemblies 8,9 can be
modified and varied without departing from the scope of protection defined by the
independent claims as a result.
[0066] In particular, the arms 21 and heads 10,43 can have different shapes and geometries
from those indicated, for example in order to support a different number of closing
elements.
[0067] In addition, the transmissions 30 could be provided with both motors 35 and transmissions
47 so as to be capable of manual operation in any operating condition including failures
of the electrical control.
1. A handling unit (13) for moving at least one mold closing element of a machine for
forming glass articles, the handling unit (13) comprising:
- a frame adapted to be fixed to a fixed structure of the machine;
- a shaft (16) having a vertical axis (18);
- a drive device (K) for motorizing and moving said shaft (16) with a roto-translatory
motion along said vertical axis (18) relative to said frame;
- an arm (21) protruding in a cantilever manner from said shaft (18) and configured
to support said closing element; and
- coupling means which couple said arm (21) to said shaft (16),
characterized in that said coupling means comprise a mechanical adjustment transmission (30) for continuously
adjusting the vertical position of said arm (21) along said shaft (16) according to
the height of the mold.
2. The handling unit according to claim 1, characterized in that said mechanical adjustment transmission (30) comprises a drive shaft protruding outside
said arm (21) and manually operable from the outside.
3. The handling unit according to claim 1 or 2, characterized by comprising an electric motor (35) for driving said mechanical adjustment transmission
(30), and a command and control unit (40) for controlling said electric motor.
4. The handling unit according to claim 3, characterized in that said command and control unit (40) comprises memory means storing, for each said
mold mountable on said machine, a respective reference position in height for said
closing element, and command and control means for controlling said electric motor
and moving said closing element into the reference position corresponding to the mold
mounted on the machine.
5. The handling unit according to claim 3 or 4, characterized in that said electric motor (35) is arranged above a free upper end of said shaft (16).
6. The handling unit according to any one of the preceding claims, characterized in that said mechanical adjustment transmission (30) is a screw transmission or a toothed
transmission.
7. The handling unit according to any one of the preceding claims,
characterized in that said coupling means furthermore comprise a slide freely sliding in opposite directions
along said shaft (16), and wherein said mechanical adjustment transmission (30) comprises:
- a screw arranged outside said shaft (16) and coupled to said shaft (16) in a rotatable
manner about its axis and in an axially fixed position, and
- a nut screw engaged by said screw and coupled to said slide in a vertically and
angularly fixed position with respect to said slide.
8. The handling unit according to claim 7,
characterized in that said mechanical adjustment transmission (30) comprises an attachment bracket having:
- an anchorage portion arranged resting on an upper end of said shaft (16) and
- an attachment portion protruding in a cantilever manner from said anchorage portion;
said screw being coupled to said attachment portion in a rotatable manner and in an
axially fixed position.
9. The handling unit according to any one of the preceding claims, characterized in that said coupling means furthermore comprise a slide freely sliding in opposite directions
along said shaft (16), and wherein said arm (21) comprises an end portion couplable
to said closing element and an end attachment portion opposite said end portion; a
quick-change releasable coupling being interposed between said end attachment portion
and said slide.
10. The handling unit according to claim 9,
characterized in that said releasable coupling comprises:
- a vertical guide parallel to the vertical axis (18) of said shaft (16) and carried
by said slide and
- a further slide carried by said end attachment portion and couplable from above
to said guide;
locking means being provided to lock said further slide on said guide in a fixed vertical
position.
11. The handling unit according to any one of the preceding claims, characterized in that said coupling means furthermore comprise a slide freely sliding in opposite directions
along said shaft (16), and wherein the handling unit (13) comprises motorized locking
means for locking said slide along said shaft (16) and are operable remotely.
12. A closing assembly for closing at the top and at least partially a forming mold of
a machine for forming glass articles; the closing assembly comprising an attachment
head, at least one closing element coupled to said attachment head and configured
to couple with said mold for closing at least partially said mold, and a handling
unit for moving said attachment head; characterized in that said handling unit is as claimed in claim 1.
13. A forming machine for producing hollow glass articles, the machine comprising at least
one forming section for forming hollow glass articles; the forming section comprising:
- a blank mold which can be chosen from a plurality of blank molds different from
one another and comprising at least one forming cavity for a glass blank;
- a finishing mold which can be chosen from a plurality of finishing molds different
from one another and comprising at least one finishing cavity for said blank and,
- for each said mold, a respective closing assembly for completely or partially closing
a top opening of the respective cavity;
at least one of said closing assemblies being as claimed in claim 12.
14. The machine according to claim 13, characterized in that each said mold comprises a relative said motorized closing assembly; an electronic
command and control unit being provided to control all of said closing assemblies
in response to a mold change program.